Draft gauge



July 25, 1933. I... M. ELLISON 1,919,713

DRAFT GAUGE Filed Sept. 21, 1932 2 Sheets-Sheet 1 INVENTOR.

5275 JV. E//i50/7 W W M, cMVW, ATTORNEY;-

July 25, 1933. M ELLISON DRAFT GAUGE Filed Sept. 21, 1932 .nlllllh.

- 1 v I 1 1 i 2 Sheets-Sheet 2 III ll vl INVENTOR.

LEW/5 M 5 5150/7 WWW w 1M W ATTORNEY;

Patented July 25,1933 v v I l UNITED i m-"Es: OFFICEYVTZEF w f r Lnwrs mtutmsoiusor mm tt, tumors it A I I nnhrr G AUGE v v Agateeaaedse e teiti,11932. Serial No. 634,125. A u This invention items] to furnace draft through thestem of the valve to show the lon gauges of the sealedgasometer bell type. gitudinal vent passages therein.

l The main object of the invention is to pro- As shown inlthe drawings, the gauge com.- vide valve; means in association with the bell prises a box-like outer casing having a body ,7

and'the .vdraft tube extending into the same section 1 and a removable cover section 2.

for automatically venting the bell to the at- The latter constitutes the frontwall of the lnosphere and'closing the tube to shut off the casingfand is. detaohably secured thereto by draft to the bell under periods of excess mimarginally disposed screws 3 as shown. The nus pressures or drafts produced in thebell cover section isprovided with a pairof sight 19 during the operation of thegauge so as to reopenings 4, 5 arranged one. above the other, lieve such pressure and prevent'the sealing vthe'opening 4 permittinga view to be had liquid at the lowerend of the bellibeing into the casing to ascertain the level of the drawn out of'the same through the tube. oil in the pan or reservoir 6 loeated within A further object'of the invention is to have thecasing for the inverted gasometer bell? the valve means carried'by'the bell above the with which the valve means ofimy invention tube so thatthe valve will act to open the bell l3 employed. t r and close the tube on the lowering of the bell The opening 5pfermitsayiew-Ito be had-of sufficientlyv to seat the valve on the tube. thesCalejS over which moves a pointerl9 at Another object 'of the invention is to prothe, outer or free end of anv arm Ill-connected vide the valve means with valve members in t0 and movable by a lever 11 fulcrumed bethe'form of discs on opposite sidesof'the head tween its ends within the casing above the of' the bell and respectively controlling the bellifas shown in Figs. 2 and 3. The; scale vent opening in the bell head and the open- Sfis referably marked on a strip of. card ing at the upper end of the draft tube Withl 0. other e.s ee i lwhich in the bell. g 1 u is mounted in a holder 12 secured in the ease A further object of the invention is to con.- g t0 h ar of the Y S W nect the valve members by a stem extending Shown. A transparent plate 14 of glass-or through the opening in the bell head, wherether suitable material covers the outer end by the valve means isin theform ofa single of thebody section 1 and is held in place by so fixture capable of a' dou'ble action in'fsealing h CQVer as. shown in Fig. 3. a p J the bell under normal minus pressures and e l 7 is suspended from One d f h venting the b ll and closing the tube under lever 11 y ay ;W -es h i F g periods of excess minus pressures. Y and hung onastud 16 fixed to and prov The 1nVeI1ti0I1 consistsfurther in the feat- J tmg laterally f om on sid o th e r s 35 tures hereinafter described and claimed. The y ke has P I g Twelve ud In 'the'accompanying drawings: H p and the latter is provided between its ends Fig. 1 is afront view f draft gauge mwith a reduced portion. providing a knifebody in'g the double'acting valveof my inveng e ing f the y The'alms 17, :1 tlon; T I I x (if the yoke are secured at their lowerends, as 40 Fig. 2'is a view looking into the gauge ith by screws 18, to the top wall or head 19 of the cover section removed, parts of the gauge the bell. Said head, as shown, is in the form r structure being broken away and in section O a fi g dc pfi o t eupp 6nd 10f respectively. for th purpose f illu t ti the bell and'is hermetically sealed thereto;

Fig. 3 is a vertical sectional view taken on h IYBIId of the bell, whichis p I 45 line 3+3 ()1? Fig, 2; u I g I I extends into the reservoir6 and is sealed Fig. lis aview showing the valve in dra ft a body of oil or other sealing liquid con:- tube closing and bell venting position; tained therein. A draft tube 20 extends up- -F1g. 5 1s a vertical sectionalvie'wftaken on Iwa'rdlyj into the. bell from. the reservoir g-. 3. a d through the liquid-seal and terminates short Fig. 6 1s a horizontal sectional view df'the bell'head; Said tube extends to the fits the opening to hold the valve central with respect to the bell and is. provided with-longitudinal grooves 23 to vent the bell to the atmosphere when the valve member 24; at the of excess minus drafts;

upper end of the stem and exterior of the bell uncovers the opening in the bell head as shown in Figs. 4 and 5, At this time the valve member 25 at the lower end of the stem and within the bell'is seated on the upper, end of the draft'tube, The valve InembersQ l, 25 are at the opposite ends of the stem 22 and are in the form of discs to seat on theedgesof the openings which they respectively control. The bell head I9 is pressed upward into tubular-form about the opening 21 to provide a more effective seating surface for the valve member for suchopening. The upper end ,of the draft tube maybe inade adjustable by providing it the form of a sleeve 20 having threaded connection with the tube.

The gauge of the drawings is designed for minus pressures. In the normal o1:;er'a tion; of the'gauge, 'thevalve iscarri'ed'by the bell above 'aiid out of contact with the draft tube 20 The opening 21 in'the bell head isc'l'osed at this time'by thefupper' member2 l seating onthe bell head about the opening, as shown'in Fig. 2. Thus the interior of the bell is closed tothe atmosphere and it may rise and lower in response to the changes of minus pressure produced "within the bell throu h the'tube 20. The bell may move within t e scale range of the gauge without disturbing the position, of the valve closing the opening in the top of the 'bell; (hen the interior of the bell is subjectedjto an excessive minus pressure, thebell'lowersjbelow the range of itsno'rmal movementand carries the valve into con tact-withthe 'u J'per" end of draft/tube 20,clos'ing the same an (shutting ofl'thepres sure to the'belli, This transfers the support of the valve from the. bell to the tube, and permits'the' bell'to lower with. respect to the valve. As the, bell; lowers, it moves away from the valvemember 2d 'uncovering open ing'21 and. venting the interiorof the bell to the atmosphere, This relieves the pressure within the bell, and theliquid which hasv been unduly raised above the seal is prevented from rising far enough to reach the upper end of the, draft tube. "Thus no opportunity is afforded for'drawing the'oil out of the seal through they draft tube undertheseperiods en pressur W 't nth h ll is relieved. the bellqrisesaud.

lifts the valve from the tube. This closes the interior of the bell to the atmosphere, and the bell is conditioned for normal operatlon,

if the excess pressure has subsided. The advantages of the double check valve are that the bell is relieved of excess minus drafts or pressures whenever they occur, and drawing of the sealing liquid out of the bell through the draft tube is prevented. Thus the gauge maybe built within practical limits, as the bellanddraft. tube need not be made unduly long to compensate for what would be the maximum rise of liquid in the bell under a maximum excess minus draft.

The fulcrum 26 for the lever 11 is supported by a bracket 27 secured to and depending from thetop wall of the casing section 1. Thelever is provided with; a counterweight 28 at its end opposite the bell,' and the pointer arm has a gravity load 29' as in gauge devices of this general character. The reservoir is filled through a fillin tube 30 which extends through the top val ve of the casing, said tube having a closing cap at its outer end as shown. The reservoir has a drain fitting 31 at itsbottom wall, said fitting being normally closed'by a cap as shown.

The details'of construction and arrangement of parts shownand. described may be variously changed and modified without depa ng from the pilrit and. sc peof my invention exeeptas pointed'out in the appended claims, I

I claim as my invention:

V 1. In'a draft gauge of the character describedhaving an' indicating mechanism, an inverted gasometer bell for actuatin the same, a liquid seal forthe lower end of the bell, a draft tube opening. into the'bell above the seal, a vent opening in the'bell above the tube, and valvemeans carried by the bell and normally closing the vent openingtherein when supported by the hell out of contact with the tube, said valve means acting toclose the tube when brought into, contact therewith in the depression of the bell by an excess minus pressure therein and opening the vent in the bell torelieve saidv pressure to prevent drawing of the sealing liquid out of the bell through the tube.

2. In a draft gauge of thehcharacter. described having an indicating mechanism, an

inverted gasometer bell for actuating the through the tube, the head of the bell about the vent opening being projected into tubu-c the seal, and valve means carried by the bell above the tube, said valve means having a stem extending through a vent opening in the head of the bell and disc-like members at the opposite ends 0i? said stemjfor opening and closing the upper end'of the tube and the vent opening, respectively. I V

LEWIS I M." ELLISON. 

